Rotary brush including stationary guide means with slidable bearing means

ABSTRACT

A rotary brush for applying paint to surfaces comprises a housing, a rotatable hollow cylindrical body which bears on the cylindrical surface a plurality of brush units, motor means, passage means for supplying paint from a supply channel to the bristles of the brush units, and a number of stationary guide rings mounted rigidly in the housing and guidingly surrounding the rotatable cylindrical body. The guide rings are disposed in zones transverse to the axis of the cylindrical body and distributed over the length of the same. Each ring bears a slidable bearing means adapted for bearing, for instance with a loose wheel at its free end, against the surface to be painted, thus relieving pressure of the bristles on the surface to be painted.

SUMMARY OF THE INVENTION

The instant invention refers to a brush specially designed to paintlarge planar surfaces, in a reduced time and applying paint layerssimilar to those obtained with conventional manual brushes. Theinvention consists of a cylinder rotatably around a coaxial hollowshaft, which, through holes provided in all its length, suppliespressurized paint to said cylinder; further including a plurality ofremovable brushes around said cylinder which are provided with means forpassing paint from the cylinder to the brush hairs. This assembly isrotatably mounted in an open housing, having an elongated opening in alongitudinal side, and is connected to a support handle and to a drivemeans coupled to the cylinder; the assembly further comprisingpressurized paint supply channels and power channels for the motor, saidmotor having command means preferably located in the handle.

PRIOR ART

For painting large surfaces, which generally are planar or similarwalls, devices are known which comprise the use of brushes, rollers orsprayers. The paint applied with brushes and rollers is more effectivedue to the better penetration of such paint, but its application isslow, thus resulting in high labor expenses. On the other hand, theapplication of paint with sprayers has lower labor costs and is faster,but the penetration is sometimes not enough. Due to the above reasons,the problem of painting large surfaces has not as yet beensatisfactorily solved.

ADVANTAGES OF THE INVENTION

The rotary brush of the instant invention permits applying paint with apenetration equivalent to that of the traditional manual brushes androllers, and as fast as with spraying means. Therefore, this novel brushhas all the advantages of the conventional systems: good penetration,rapidity, uniformity and lower labor costs.

NOVELTY OF THE INVENTION

The device of the present invention is based on a new functionalarrangement which could be carried out in several different ways.Basically, the invention consists of a hollow body, elongated androtatable about its axis, which body is rotatably mounted in anelongated housing; on the external surface of the body there are severalbrush units formed by soft hairs supported in elongated base memberswhich have open channels or grooves in their bottom or inner sides inorder to allow the passage of liquid paint from the interior of saidhollow body to the interstices between the hairs, the body thus forms arotor driven by means of a driving unit. Said driving unit is capable ofslowly rotating the hollow body and brush units. This driving unit canbe an appropriate electric motor, preferably associated to a speedreducer. As an alternative, the driving unit may be a blade turbinedriven by compressed air. The hollow body rotates about a coaxial shaftwhich is also hollow and, on one of its ends is coupled to a ductsupplying pressurized paint, while the other end is closed. The paintpasses from the hollow shaft to the interior of the holloww body throughholes distributed over the entire length of the hollow shaft.

The assembly formed by the hollow body, inner shaft, brushes and drivingunit is mounted in a motor casing, said driving unit being locatedoutside the housing, said housing having a large opening in thelongitudinal sleeve wall thereof, through which the brush units appearwhen the hollow body rotates. Besides, such assembly is supported by atubular handle by means of which the operator holds the assembly. Paintchannels and power ducts pass through the mentioned handle. The supplychannels are tubes, one for each equipment, which extend from a drivingpump associated to a reservoir in a conventional manner, including acheck valve preferably located in the hilt of the handle. The ductsproviding power to the driving means may be insulated electric leadslocated also in the interior of the handle, there being a switch on thehilt of the handle. The possibility exists of including a reversedriving device which may be located in the hilt or in the housing. Alsocompressed air tubes may pass through the handle.

The assembly described above is supplemented by bearing means slidablewith respect to the surface to be painted, which may include pressuredampers for controlling brush friction on the surface to be painted. Thebearing means are supported by rings mounted stationary in the housingand surrounding the hollow body and also serving as guide means for saidhollow body. Said rings may have ball or roller bearings in order toreduce the pressure of the brushes on a surface being painted.

Each of the brush units has a base member with a cavity, channel orgroove, open toward the interior of the hollow body in order that thepaint deposited in said hollow body may abundantly enter the cavity.Opposite to the cavity in the base member of each brush there is aplurality of holes, and a capillary tube connected to each of them,having a length lower than that of the hairs. These tubes are mixed withsaid hairs so that the paint, which is pressurized from the cavity, maysaturate all hairs of each brush unit. As a convenient accessory, it isadvisable to locate a filter in each of the above mentioned cavities,for example a felt extended on the bottom of each cavity.

As optional features, the central shaft may rotate along with thecylinder, or be a fixed element in which case said cylinder will rotateon bearings around the shaft and would be directly coupled to thedriving means. Further, the handle of the device may be articulated,thereby providing the vertical displacement of the housing needed inorder to apply paint horizontally.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other advantages of the invention will be apparent forthose skilled in the art in the light of the following detaileddisclosure taken in conjunction with the attached drawings, which arenot intended to limit the scope of the invention but to illustrate anexample of same, and in which:

FIG. 1 is a perspective view of a rotary brush according with thepresent invention;

FIG. 2 is a cross section of the brush of FIG. 1;

FIG. 3 is a detailed cross sectional view corresponding to one of thebrushes of the device of the present invention;

FIG. 4 is a perspective view of a brush, partially disassembled, with aportion of its hair cut out;

FIG. 5 is a schematic diagram representing one of the means bearing thedevice on the surface to be painted;

FIG. 6 is a sectional view of the bearing means of FIG. 5; and

FIG. 7 is a schematic view of a longitudinal section of the deviceillustrated in FIG. 1, excluding brushes and handle.

In all figures the same reference numerals refer to equal or equivalentparts or elements constituting the assembly selected as example of thepresent invention.

DETAILED DESCRIPTION OF THE EXAMPLE

As may be seen in FIG. 1, the brush of the present invention comprisesan elongated housing 1 having in its side wall between its opposite endwalls 2, 3 a wide axially extending opening through which the elongatedbrush units 4 appear, being removably mounted on a cylindric hollow body5 which is rotatable about a hollow shaft 28 supported by both oppositeends of the housing 1. Said shaft 28, along with the hollow body 5 maybe driven by a motor means 6 mounted on the outside of end wall 2 andprotected, preferably, by a cover 6a. This assembly is attached to atubular handle 7 which has a hilt 8. In the interior of said handlethere is a channel 9 which supplies pressurized liquid paint in order tofill the hollow body 5 and also duct or line 10 supplying power to themotor means 6.

In the hilt 8 there is a command button 11 which actuates a check valvelocated in the channel 9. The hilt has also a switch 12 turning on oroff power flow through duct 10. If the motor means 6 consists of anelectric motor-and-speed reducer unit, the duct 10 will be constitutedby electric leads, whereas if the mentioned motor means is a compressedair turbine, the duct 10 will be a tube supplying compressed air from acompressor (not shown).

On the other hand, the supply of pressurized paint through channel 9will be from a conventional pump 13 or from a compressor associated to areservoir 14, the details of which are not shown. Reference numeral 15indicates a button or switch used for reversing the action of the motormeans 6. If such motor means is an electric motor, the switch 15 will bea reversal switch, and if the motor means is a turbine, the switch 15will be capable of selectively directing a compressed air inlet conduitin order to match with the different positions of the turbine blades, sothat the turbine may rotate in both directions.

The rotary cylindrical body 5 is held in the housing 1 by twosurrounding guide rings 16 mounted stationary in two intermediate zonesin the housing 1, for instance, by means of cross-pieces 17. Each guidering 16 carries a bearing assembly comprising a support element 18 and,slidably mounted therein, a bearing arm 19 which bears at its free end awheel 20 acting as a limiting element to the penetration degree of thebrush hairs 4 in the surface to be painted and on which surface saidwheels 20 rest.

FIGS. 5 and 6 represent, in more detail, the above mentioned bearingassemblies. It may be seen that the supports 18 include expansionsprings 21 capable of damping the pressure exercised on the surface tobe painted. As an alternative, rings 16 include ball or roller bearings22 mounted on an internal race 23 adjusted to the outer surface of thehollow cylindric body 5.

Brush units 4 are removably mounted on guide rails 24 provided alonggeneratrixes of the cylindric body 5, as illustrated in FIG. 3. Thebrush units may extend longitudinally, and the base members 25 of eachbrush 4 may be inserted in the groove of its guide rail 24. The basemember 25 of each brush unit 4 has a cavity on its underside in whichcavity a piece of felt 26 can be logded, which piece of felt acts as afilter in front of the entry orifices of capillary tubes 27 which inturn penetrate between the hairs of each brush 4.

In FIG. 7 it may be seen that the rotary cylinder 5 is mounted on acentral hollow shaft 28 provided in its cylindrical wall with aplurality of holes or openings 29 which communicate via the hollowinterior of shaft 28 with the tubing supplying pressurized paint, whichis located in the handle 7. A pin or key 30, or any equivalent means,connects said hollow shaft 28 with the cylinder body 5 so that both mayrotate at the same time. As an alternative, without the use of said pin30, the assembly may have a fixed shaft and a cylinder coupled to themotor.

While in the present embodiment of the invention, in FIGS. 1 and 2,three rows of brush units have been included, there are otherembodiments in which the number of rows may be increased or decreased,without any variation in the intended scope of the invention. Further,in FIG. 1 a discharge spout 31 is included in order to remove from thehousing paint deposits spilled by the action of the brush units. On theends of the central shaft 28 and related to end walls 2 and 3 of thehousing, bearing means (not shown) could be provided. The mounting ofsaid shaft 28 may be carried out with a known nut 32 in order tofacilitate the dismantling of the apparatus.

Additional bearing means making contact with the surface being paintedcan be rigidly attached, in a manner known per se, e.g., from U.S. Pat.No. 691,184 to Heinrich Schickler, to the opposite end walls of thehousing which contains the cylindrical body and brush units.

When building the rotary brush of the present invention, furthermodifications may be introduced, for example in the motor command means,in the number and distribution of brush units around the cylinder body5, in the shape of the housing 1, the coupling of the central shaft 28and the cylindrical body 5 to the motor, inclusion of a screw adjustablearticulation for vertical positioning of the housing etc, without goingbeyond the scope of the present disclosure which is basically determinedby the following claims.

What is claimed:
 1. A rotary brush comprising:a housing having two endwalls, a longitudinal sleeve wall therebetween, and a large opening insaid sleeve wall extending longitudinally between said end walls; ahollow cylindrical body mounted rotatably in said housing between saidend walls thereof and having a cylindrical wall; a plurality of brushunits mounted on the outer surface of said cylindrical wall of saidcylindrical body, each of said brush units comprising bristles extendingradially with regard to said cylindrical body, and appearing throughsaid large opening in said housing sleeve wall; motor means mounted onthe outer face of one of said end walls and being coupled to saidcylindrical body for imparting rotary movement thereto; paint-supplymeans connected to the interior of said hollow cylindrical body andadapted for supplying pressurized liquid paint to said interior and topassage means in said cylindrical wall of said cylindrical body, leadingfrom said interior of the latter to between said bristles of said brushunits, and being adapted for passing liquid paint on to said bristles; anumber of stationary guide rings rigidly mounted inside said housing intransverse zones arranged in spaced relationship to one another and tosaid end walls of said housing and guidingly surrounding saidcylindrical body; and radially slidable bearing means mounted on saidstationary guide rings to project outwardly from said large opening ofsaid housing, said radially slidable bearing means being adapted forbearing against a surface to be painted and limiting contact pressure,at points distributed over the length of said cylindrical body of thebristles of the respective brush units which are in contact with saidlast-mentioned surface.
 2. The rotary brush of claim 1, furthercomprising a hollow shaft coaxial with and fixedly supporting saidcylindrical body for rotation therewith, said hollow shaft beingconnected to said passage means and being in driving engagement withsaid motor means, and having a cylindrical shaft wall provided withperforations through which paint can pass from the interior of saidhollow shaft to the interior of said hollow cylindrical body.
 3. Therotary brush of claim 1, wherein each of said slidable bearing meanscomprises a retractable arm, resilient means for counteractingretraction of said arm so as to damp the same, and a convex tire wheelmounted freely rotatably on the free end of said arm and adapted forcontacting said surface to be painted.
 4. The rotary brush of claim 1,wherein each brush unit comprises an elongated bristle-carrying basemember having a cavity in the underside thereof facing toward saidcylindrical body, and a number of holes in said base member forestablishing communication between said cavity and the outer side ofsaid base member carrying said bristles, said holes being part of saidpassage means.
 5. A rotary brush, as claimed in claim 4, wherein acapillary tube, the length of which is less than the length of thebristles, is attached to the bristle bearing outer side of said basemember to register with each of said holes.
 6. A rotary brush as claimedin claim 4, wherein a filtering element constituted by a band of thickfelt is located in the cavity of each base member in front of said holestherein.
 7. A rotary brush, as claimed in claim 1, wherein each guidering comprises rotary bearing means comprising two concentric racesbetween which there is a plurality of balls or rollers.